A bomb has exploded near a bus carrying a group of Jordanian writers who met with senior Syrian government leaders on an official visit, wounding five of them, one of the delegates says.

The Jordanians said five of them were wounded by the late Thursday explosion in Daraa Province, 40 kilometers (25 miles) east of the Jordanian border.

"It was tumultuous. We heard a big boom and we were hit with shrapnel," said Hussein Mutawee, one of the wounded writers.

He said the 20-member delegation from the Jordanian Writers Syndicate was in Syria for four days, meeting with top officials. They had plans to meet President Bashar Assad, but the government "told us the president was busy," Mutawee said.

Mutawee accused the so-called Free Syrian Army (FSA) of intentionally targeting his group.

"As soon as we chanted, 'Long live President Bashar,' there was a boom," he said.

Some Jordanian unionists, especially those with pan-Arab nationalist sentiments, support Assad because they believe that the war is a conspiracy hatched by the United States and Israel to weaken Arabs.

Roadside bomb attacks are common in Syria's nearly three-year conflict that activists say has killed more than 100,000 people.